Notification device

ABSTRACT

A notification device includes a calculation unit calculating, based on a speed of a vehicle, a vehicle stoppage distance by which the vehicle travels until the vehicle enters a stopped state while performing autonomous driving, a notification unit performing notification about information with respect to an outside of the vehicle, and a notification controller causing the notification unit not to perform notification about information indicating that the vehicle is in the middle of deceleration until the vehicle passes by a first soon-to-cross pedestrian and to cause the notification unit to perform notification about the information after the vehicle passes by the first soon-to-cross pedestrian when a distance between the vehicle and the first soon-to-cross pedestrian is smaller than the vehicle stoppage distance and a distance between the vehicle and a second soon-to-cross pedestrian is equal to or greater than the vehicle stoppage distance.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based on Japanese Patent Application No. 2018-191841filed with Japan Patent Office on Oct. 10, 2018, the entire contents ofwhich are hereby incorporated by reference.

TECHNICAL FIELD

The present disclosure relates to a notification device.

BACKGROUND

U.S. Pat. No. 9,196,164 discloses a vehicle performing autonomousdriving. When a determination is made that a pedestrian may cross thetrajectory of the vehicle, the vehicle notifies the pedestrian of acurrent or future behavior of the host vehicle by using a language,light, a sound, or the like.

SUMMARY

In the case of the device described in U.S. Pat. No. 9,196,164, whenthere is a plurality of pedestrians determined as pedestrians who maycross the trajectory, there is a possibility that the pedestrians cannotbe appropriately notified of the behavior of the vehicle. For example,there is a case where the vehicle detects a first pedestrian and asecond pedestrian positioned further than the first pedestrian and thevehicle stops at the position of the second pedestrian after passingthrough the position of the first pedestrian while decelerating. Whenthe vehicle performs notification about the deceleration while startingthe deceleration at this time, the first pedestrian may erroneouslyrecognize that the vehicle will stop in front of the first pedestrian.

The present disclosure provides a notification device that can performnotification without confusing a plurality of pedestrians.

An aspect of the present disclosure relates to a notification deviceconfigured to provide in a vehicle performing autonomous driving andconfigured to notify pedestrians of information. The notification deviceincludes a recognition unit, a determination unit, a calculation unit, anotification unit, and a notification controller. The recognition unitis configured to recognize, based on a result of detection performed byan external sensor, positions of the pedestrians in front of a roadwayon which the vehicle travels. The determination unit is configured todetermine, based on a distance between the positions of the pedestriansrecognized by the recognition unit and the road on which the vehicletravels, whether the pedestrians are soon-to-cross pedestrians. Thecalculation unit is configured to calculate, based on a speed of thevehicle during autonomous driving, a vehicle stoppage distance by whichthe vehicle travels until the vehicle enters the stopped state whileperforming autonomous driving when the determination unit determinesthat the pedestrians are the soon-to-cross pedestrians. The notificationunit is provided in the vehicle and is configured to performnotification about the information with respect to an outside of thevehicle. The notification controller is configured to determine theinformation based on the vehicle stoppage distance calculated by thecalculation unit, the position of the vehicle, and the positions of thesoon-to-cross pedestrians and to cause the notification unit to performnotification about the determined information. The soon-to-crosspedestrians include a first soon-to-cross pedestrian and a secondsoon-to-cross pedestrian positioned ahead of the first soon-to-crosspedestrian in a proceeding direction of the vehicle. The notificationcontroller is configured to cause the notification unit not to performnotification about information indicating that the vehicle is in themiddle of deceleration until the vehicle passes by the firstsoon-to-cross pedestrian and to cause the notification unit to performnotification about information indicating that the vehicle is in themiddle of deceleration after the vehicle passes by the firstsoon-to-cross pedestrian when a distance between the vehicle and thefirst soon-to-cross pedestrian is smaller than the vehicle stoppagedistance and a distance between the vehicle and the second soon-to-crosspedestrian is equal to or greater than the vehicle stoppage distance.

In the case of the notification device, when the distance between thevehicle and the first soon-to-cross pedestrian is smaller than thevehicle stoppage distance and the distance between the vehicle and thesecond soon-to-cross pedestrian is equal to or greater than the vehiclestoppage distance, notification about the information indicating thatthe vehicle is in the middle of deceleration is not performed withrespect to the outside of the vehicle until the vehicle passes by thefirst soon-to-cross pedestrian and notification about the informationindicating that the vehicle is in the middle of deceleration isperformed with respect to the outside of the vehicle after the vehiclepasses by the first soon-to-cross pedestrian. As described above, thevehicle do not start notification about the information indicating thatthe vehicle is in the middle of deceleration at a position in front ofthe first soon-to-cross pedestrian at which the vehicle will not stop.Therefore, the first soon-to-cross pedestrian can avoid erroneouslyrecognizing that the vehicle will stop in front of the firstsoon-to-cross pedestrian. In addition, after the vehicle passes by thefirst soon-to-cross pedestrian, notification about the informationindicating that the vehicle is in the middle of deceleration isperformed. Therefore, correct information indicating that the vehiclewill stop in front of the second soon-to-cross pedestrian can beappropriately provided to the second soon-to-cross pedestrian.Accordingly, with the notification device, it is possible to performnotification without confusing any one of the first soon-to-crosspedestrian and the second soon-to-cross pedestrian.

In the notification device according to the aspect of the disclosure,the notification controller may be configured to cause the notificationunit to perform notification about information indicating passage of thevehicle until the vehicle passes by the first soon-to-cross pedestrian.With this configuration, the first soon-to-cross pedestrian who is notnotified of the information indicating that the vehicle is in the middleof deceleration in the above-described situation is appropriatelynotified of a future behavior of the vehicle, that is, a behavior ofpassing by the first soon-to-cross pedestrian without stopping in frontof the first soon-to-cross pedestrian. Therefore, with the notificationdevice, it is possible to avoid confusing the first soon-to-crosspedestrian.

The notification device according to the aspect of the disclosure mayfurther include a vehicle stoppage determination unit configured todetermine whether the vehicle is in a stopped state and the notificationcontroller may be configured to change information, about which thenotification unit performs notification, from information indicatingthat the vehicle is in the middle of deceleration to informationindicating that the vehicle is in the stopped state when the vehiclestoppage determination unit determines that the vehicle is in thestopped state. With this configuration, it is possible for a pedestrianto clearly distinguish between a state where the vehicle is in themiddle of deceleration and a state where the vehicle is in the stoppedstate.

In the notification device according to the aspect of the disclosure,the notification unit may be configured to display the information asnotification about the information and the notification controller maybe configured to control a displaying operation of the notificationunit. With this configuration, it is possible to perform notificationwith respect to a pedestrian crossing a road such that the pedestriancan visually recognize the notification.

According to various aspects and embodiments of the present disclosure,it is possible to perform notification without confusing a plurality ofpedestrians.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a functional block diagram of an example of a vehicleincluding a notification device according to the embodiment.

FIG. 2A is an example of the position of a pedestrian. FIG. 2B is anexample of a position corresponding to a soon-to-cross pedestrian.

FIG. 2C is another example of the position corresponding to thesoon-to-cross pedestrian.

FIG. 3A is a view illustrating an example of an in-vehicle installationposition of a display unit.

FIG. 3B is a view illustrating another example of the in-vehicleinstallation position of the display unit.

FIG. 4 is a view illustrating an example of an operation of switchingbetween states of a displaying operation with respect to onesoon-to-cross pedestrian.

FIG. 5 is a view illustrating another example of an operation ofswitching between states of a displaying operation with respect to onesoon-to-cross pedestrian.

FIG. 6 is a view illustrating an example of an operation of switchingbetween states of a displaying operation with respect to a plurality ofsoon-to-cross pedestrians.

FIG. 7 is a flowchart illustrating an example of the operation of thenotification device.

FIG. 8 is a flowchart illustrating an example of the operation of thenotification device.

DETAILED DESCRIPTION

Hereinafter, an exemplary embodiment will be described with reference todrawings. In the following description, the same or correspondingelements are given the same reference numerals and repetitivedescription will be omitted.

Configuration of Vehicle and Notification Device

FIG. 1 is a functional block diagram of an example of a vehicle 2including a notification device 1 according to the embodiment. Asillustrated in FIG. 1, in the vehicle 2 such as a passenger car, thenotification device 1 is installed. The notification device 1 isprovided in the vehicle 2 performing autonomous driving and thenotification device 1 notifies a pedestrian of information. Autonomousdriving is vehicle control that causes the vehicle 2 to automaticallytravel to a destination set in advance. The destination may be set by anoccupant such as a driver and may be automatically set by the vehicle 2.At the time of the autonomous driving, the driver does not need toperform a driving operation and the vehicle 2 travels automatically.

The vehicle 2 is provided with an external sensor 3, a GPS receiver 4,an internal sensor 5, a map database 6, a navigation system 7, anautonomous driving ECU 8, and an actuator 9.

The external sensor 3 is a detecting machine that detects a situation inthe vicinity of the vehicle 2. The external sensor 3 detects theposition of an object in front of a roadway on which the vehicle 2travels. The external sensor 3 includes at least one of a camera and aradar sensor.

The camera is an imaging machine that images a situation outside thevehicle 2. The camera is provided on a rear side of a windshield of thevehicle 2, for example. The camera acquires imaging information relatedto the situation outside the vehicle 2. The camera may be a monocularcamera and may be a stereo camera. The stereo camera includes twoimaging units that are disposed such that binocular parallax isrealized. Imaging information of the stereo camera includes informationin a depth direction also.

The radar sensor is a detecting machine that detects an object in thevicinity of the vehicle 2 by using a radio wave (for example, millimeterwave) or light. Examples of the radar sensor include a millimeter waveradar and a laser imaging detection and ranging (LIDAR). The radarsensor detects an object by transmitting a radio wave or light to thevicinity of the vehicle 2 and receiving the radio wave or lightreflected by an obstacle.

The GPS receiver 4 acquires position information indicating the positionof the vehicle 2 by receiving signals from three or more GPS satellites.The position information includes latitude and longitude, for example.Instead of the GPS receiver 4, other means capable of specifying thelatitude and the longitude of the vehicle 2 may also be used.

The internal sensor 5 is a detecting machine that detects a travelingstate of the vehicle 2. The internal sensor 5 includes a vehicle speedsensor, an acceleration sensor, and a yaw rate sensor. The vehicle speedsensor is a measurer that measures the speed of the vehicle 2. As thevehicle speed sensor, for example, a vehicle wheel speed sensor that isprovided with respect to vehicle wheels of the vehicle 2 or a driveshaft integrally rotating with the vehicle wheels and that measures therotation speed of vehicle wheels is used.

The acceleration sensor is a measurer that measures the degree ofacceleration of the vehicle 2. The acceleration sensor may include afront-rear acceleration sensor that measures the degree of accelerationof the vehicle 2 in a front-rear direction and a lateral accelerationsensor that measures the degree of acceleration of the vehicle 2. Theyaw rate sensor is a measurer that measures the yaw rate (rotary angularspeed) around the vertical axis of the center of gravity of the vehicle2. As the yaw rate sensor, a gyro sensor can be used, for example.

The map database 6 is a storing device that stores map information. Themap database 6 is stored in a hard disk drive (HDD) installed in thevehicle 2, for example. The map database 6 includes information of astationary object, traffic rules, and the positions of traffic lights.The stationary object is, for example, a road surface painting(including lane boundary line such as white line and yellow line) and astructure (such as curb, pole, electric pole, building, sign, and tree).A part of the map information included in the map database 6 may bestored in a storing device different from the HDD in which the mapdatabase 6 is stored. A part of or the entire map information includedin the map database 6 may be stored in a storing device other than astoring device provided in the vehicle 2.

The navigation system 7 is a system that guides a driver of the vehicle2 to a destination set in advance. The navigation system 7 recognizes,based on the position of the vehicle 2 measured by the GPS receiver 4and the map information in the map database 6, a traveling road and atraveling lane on which the vehicle 2 travels. The navigation system 7calculates a target route from the position of the vehicle 2 to thedestination and guides the driver along the target route by using ahuman machine interface (HMI).

The actuator 9 is a device that performs traveling control of thevehicle 2. The actuator 9 includes at least an engine actuator, a brakeactuator, and a steering actuator. The engine actuator controls thedrive force of the vehicle 2 by changing the amount of air supplied toan engine (for example, changing throttle opening degree) in accordancewith a control signal from the autonomous driving ECU 8. The engineactuator controls the drive force of a motor functioning as a powersource when the vehicle 2 is a hybrid vehicle or an electric vehicle.

The autonomous driving ECU 8 controls the vehicle 2. The ECU is anelectronic control unit that includes a central processing unit (CPU), aread only memory (ROM), a random access memory (RAM), a controller areanetwork (CAN) communication circuit, or the like. The autonomous drivingECU 8 is connected to a network in which communication is performed bymeans of the CAN communication circuit and is connected to theabove-described constituent elements of the vehicle 2 such that theautonomous driving ECU 8 can communicate with the constituent elements.The autonomous driving ECU 8 realizes an autonomous driving function byoperating the CAN communication circuit such that data is input andoutput, storing the data in the RAM, loading a program stored in the ROMinto the RAM, and executing the program loaded into the RAM, based on asignal output by the CPU, for example. The autonomous driving ECU 8 mayinclude a plurality of electronic control units.

The autonomous driving ECU 8 recognizes an object (including position ofobject) in the vicinity of the vehicle 2 based on at least one of theresult of detection performed by the external sensor 3 and the mapdatabase 6. Examples of the object include a dynamic object such as apedestrian, a bicycle, and a non-host vehicle in addition to astationary object such as an electric pole, a guardrail, a tree, and abuilding. The autonomous driving ECU 8 performs object recognition eachtime the result of detection is acquired from the external sensor 3, forexample. The autonomous driving ECU 8 may recognize an object by usingother known methods.

The autonomous driving ECU 8 detects a dynamic object from recognizedobjects by using the information of a stationary object included in themap database 6, for example. The autonomous driving ECU 8 may detect thedynamic objects by using other known methods.

The autonomous driving ECU 8 measures the movement quantity of thedynamic object at that time by applying a Kalman filter a particlefilter, or the like with respect to the detected dynamic object. Themovement quantity includes the movement direction and the movement speedof the dynamic object. The movement quantity may include the rotationspeed of the dynamic object. In addition, the autonomous driving ECU 8may perform movement quantity error estimation.

The autonomous driving ECU 8 recognizes the traveling state of thevehicle 2 based on the result of detection performed by the internalsensor 5 (for example, vehicle speed information of vehicle speedsensor, acceleration information of acceleration sensor, yaw rateinformation of yaw rate sensor, or like). The traveling state of thevehicle 2 includes, for example, the vehicle speed, the degree ofacceleration, and the yaw rate.

The autonomous driving ECU 8 recognizes, based on the result ofdetection performed by the external sensor 3, boundary lines of a laneon which the vehicle 2 travels.

The autonomous driving ECU 8 generates the course of the vehicle 2 basedon the result of detection performed by the external sensor 3, the mapdatabase 6, the recognized position of the vehicle 2 in a map,information about a recognized object (including lane boundary lines),and the recognized traveling state of the vehicle 2. At this time, theautonomous driving ECU 8 generates the course of the vehicle 2 whilemaking an assumption about the behavior of an object in the vicinity ofthe vehicle 2. Examples of the assumption about the behavior of theobject include an assumption that all of objects in the vicinity of thevehicle 2 are stationary objects, an assumption that a dynamic objectmoves independently, and an assumption that a dynamic object moves whileinteracting with at least one of another object and the vehicle 2.

The autonomous driving ECU 8 generates a plurality of candidates for thecourse of the vehicle 2 by using a plurality of assumptions. Thecandidates for the course include at least one course along which thevehicle 2 travels avoiding an object. The autonomous driving ECU 8selects one course by using the reliabilities of the candidates for thecourse or the like.

The autonomous driving ECU 8 generates a traveling plan in accordancewith the selected course. The autonomous driving ECU 8 generates thetraveling plan in accordance with the course of the vehicle 2 based onthe result of detection performed by the external sensor 3 and the mapdatabase 6. The autonomous driving ECU 8 generates the traveling plansuch that the speed limit for a traveling lane is not exceeded by usingthe speed limit stored in the map database 6. In addition, theautonomous driving ECU 8 generates the traveling plan in which thevehicle 2 travels such that a predetermined upper limit speed is notexceeded.

The autonomous driving ECU 8 outputs the traveling plan to be generatedsuch that the course of the vehicle 2 has a plurality of combinations oftwo elements, the two elements being a target position p in a coordinatesystem fixed to the vehicle 2 and a speed V at each target point (thatis, plurality of configuration coordinates (p, V)). Here, each targetposition p includes at least the X and Y coordinates thereof in thecoordinate system fixed to the vehicle 2 or information equivalentthereto. Note that, the traveling plan is not particularly limited aslong as the traveling plan described the behavior of the vehicle 2.Regarding the traveling plan, a target time t may be used instead of thespeed V and the target time t and the orientation of the vehicle 2 atthat time may be added to the traveling plan. The traveling plan may bedata indicating how the vehicle speed, the degree of acceleration anddeceleration, the steering torque, and the like of the vehicle 2 changewhen the vehicle 2 travels along the course. The traveling plan mayinclude the speed pattern, the pattern of the degree of acceleration anddeceleration, and the steering pattern of the vehicle 2.

The autonomous driving ECU 8 automatically controls travel of thevehicle 2 based on the generated traveling plan. The autonomous drivingECU 8 outputs a control signal corresponding to the traveling plan tothe actuator 9. In this manner, the autonomous driving ECU 8 controlstravel of the vehicle 2 such that the vehicle 2 automatically travels inaccordance with the traveling plan.

Hereinafter, autonomous driving that is performed by the autonomousdriving ECU 8 is explained when a pedestrian is present in front of aroad on which the vehicle 2 travels.

The autonomous driving ECU 8 recognizes, based on the result ofdetection performed by the external sensor 3, the position of thepedestrian in front of the roadway on which the vehicle 2 travels. Theautonomous driving ECU 8 determines whether an object detected by theexternal sensor 3 is a pedestrian or not by using a pattern matchingtechnique or the like. FIG. 2A is an example of the position of thepedestrian. In an example shown in FIG. 2A, the vehicle 2 is travelingalong a road R. A pedestrian H is present at a position (for example,position ahead of position P0 of vehicle head in proceeding direction)in front of the roadway on which the vehicle 2 travels. The externalsensor 3 detects boundary lines of the road R and an object present at aposition PH and the autonomous driving ECU 8 recognizes that the objectpresent at the position PH is the pedestrian H.

The autonomous driving ECU 8 determines whether the pedestrian H is asoon-to-cross pedestrian based on a distance between the position PH ofthe recognized pedestrian H and the road R on which the vehicle 2travels. The soon-to-cross pedestrian refers to a pedestrian who has anintention to cross a road. In the example shown in FIG. 2A, thepedestrian H is separated from a boundary line of the road R by adistance W. The autonomous driving ECU 8 determines that the pedestrianis the soon-to-cross pedestrian when the distance W is equal to or lowerthan a threshold value, for example. A determination unit 12 determinesthat the pedestrian H is not the soon-to-cross pedestrian when thedistance W is not equal to or lower than the threshold value, forexample. The autonomous driving ECU 8 may determine whether thepedestrian H is the soon-to-cross pedestrian in consideration of adirection in which the face of the pedestrian H faces and a direction inwhich the pedestrian H moves as well. The autonomous driving ECU 8determines that the pedestrian is not the soon-to-cross pedestrian whenthe pedestrian H moves in a direction away from the road R. Theautonomous driving ECU 8 may determine whether the pedestrian H is thesoon-to-cross pedestrian in consideration of a distance between thepedestrian H and a pedestrian crossing as well.

The autonomous driving ECU 8 continues the autonomous driving when thepedestrian H is not the soon-to-cross pedestrian. The autonomous drivingECU 8 determines the position corresponding to the soon-to-crosspedestrian on the road R when the pedestrian H is the soon-to-crosspedestrian. The autonomous driving ECU 8 draws a straight line from theposition of the soon-to-cross pedestrian to the course of the vehicle 2and determines an intersection between the straight line and the courseas the position corresponding to the soon-to-cross pedestrian, forexample. The position corresponding to the pedestrian is a position onthe road that is determined based on the position of the pedestrian andis a position used when a behavior such as stoppage is performed inaccordance with the pedestrian at the time of the autonomous driving.The autonomous driving ECU 8 may determine the position corresponding tothe soon-to-cross pedestrian in consideration of a direction in whichthe soon-to-cross pedestrian moves as well. FIG. 2B is an example of theposition corresponding to the soon-to-cross pedestrian. In FIG. 2B, asoon-to-cross pedestrian H1 is about to move in a direction orthogonalto the road R. In this case, as shown in FIG. 2B, a straight lineextending from the position PH of the soon-to-cross pedestrian H1 in adirection in which the soon-to-cross pedestrian H1 moves is drawn and anintersection between the course of the vehicle 2 and the straight lineis determined as a position P1 corresponding to the soon-to-crosspedestrian H1. FIG. 2C is another example of the position correspondingto the soon-to-cross pedestrian. In FIG. 2C, the soon-to-crosspedestrian H1 is about to move in a direction obliquely intersecting theroad R. In this case, as shown in FIG. 2C, a straight line extendingfrom the position PH of the soon-to-cross pedestrian H1 in a directionin which the soon-to-cross pedestrian H1 moves is drawn and anintersection between the course of the vehicle 2 and the straight lineis determined as the position P corresponding to the soon-to-crosspedestrian H1.

The autonomous driving ECU 8 calculates, based on the speed of thevehicle 2 during autonomous driving, a vehicle stoppage distance bywhich the vehicle 2 travels until the vehicle 2 enters a stopped statewhile performing autonomous driving. The stopped state is a state wherea determination is made that the vehicle 2 is stopped based on theresult of detection of the internal sensor 5. The autonomous driving ECU8 determines that the vehicle 2 is in the stopped state when the vehiclespeed measured by the internal sensor 5 is zero or falls in apredetermined range including zero. That is, the stopped state refers acase where the vehicle 2 is moving such that the vehicle 2 can beregarded as being stopped in addition to a case where the vehicle 2 iscompletely stopped.

The autonomous driving ECU 8 can calculate, based on the vehicle speedmeasured by the internal sensor 5 and the braking performance of thevehicle 2, the vehicle stoppage distance by which the vehicle 2 travelsfrom the current position until the vehicle 2 in a traveling stateenters the stopped state, for example. The autonomous driving ECU 8 mayacquire the braking performance of the vehicle 2 from specificationinformation of the vehicle 2 or may determine a braking force that thevehicle 2 can exhibit in consideration of the current travelingsituation of the vehicle 2. For example, when the current travelingsituation of the vehicle 2 is a traveling situation in which it ispossible to brake quickly, the autonomous driving ECU 8 determines tocause the vehicle 2 to enter the stopped state with a braking force thatreaches the upper limit value of the braking performance of the vehicle2. When the current traveling situation of the vehicle 2 is not atraveling situation in which it is possible to brake quickly, theautonomous driving ECU 8 determines to cause the vehicle 2 to enter thestopped state with a braking force lower than the upper limit value ofthe braking performance of the vehicle 2 in consideration of a distancebetween the vehicle 2 and a non-host vehicle, ride quality with respectto an occupant, or the like.

The autonomous driving ECU 8 calculates a pedestrian-to-vehicle distancewhich is a distance between the position P1 corresponding to thesoon-to-cross pedestrian H1 and the current position P0 of the vehicle 2(for example, position of vehicle head of vehicle 2). When thepedestrian-to-vehicle distance is equal to or greater than the vehiclestoppage distance, the autonomous driving ECU 8 determines that thevehicle 2 can be stopped before the vehicle 2 reaches the position P1.The autonomous driving ECU 8 causes the vehicle 2 to decelerate at aposition in front of a position at which the pedestrian-to-vehicledistance is smaller than the vehicle stoppage distance. The autonomousdriving ECU 8 determines that the vehicle 2 cannot be stopped before thevehicle 2 reaches the position P1 when the pedestrian-to-vehicledistance is smaller than the vehicle stoppage distance. In this case,the autonomous driving ECU 8 causes the vehicle 2 to pass through theposition P1 corresponding to the soon-to-cross pedestrian H1. Note that,when the vehicle 2 is caused to pass through the position P1corresponding to the soon-to-cross pedestrian H1, the autonomous drivingECU 8 may cause the vehicle 2 to decelerate.

The notification device 1 is provided with a notification ECU 10 and adisplay unit 16 (example of notification unit). The notification ECU 10is an electronic control unit that controls notification of informationwith respect to a pedestrian. The notification ECU 10 may include aplurality of ECUs. The display unit 16 is a machine that is provided inthe vehicle 2 and that performs notification of information with respectto the outside of the vehicle. The display unit 16 is connected to thenotification ECU 10 and displays information based on an output signalof the notification ECU. The information is information which apedestrian in a proceeding direction of the vehicle 2 is to be notifiedof and is information indicating the current traveling state of thevehicle 2, for example. Examples of the traveling state include atraveling continuation state where the vehicle 2 continues to travel, adeceleration state where the vehicle 2 is in the middle of deceleration,the stopped state where the vehicle 2 is stopped, a movement startingstate where the vehicle 2 starts to move, and a passage state where thevehicle 2 passes through a position corresponding to a pedestrian, forexample.

The display unit 16 is a light source device such as a lamp, forexample. The display unit 16 is disposed at a position such that thedisplay unit 16 can be visually recognized from a position in front ofthe vehicle 2. FIG. 3A is a view illustrating an example of thein-vehicle installation position of the display unit. As shown in FIG.3A, one display unit 16 is provided in a grille portion on the frontside of the vehicle 2. FIG. 3B is a view illustrating another example ofthe in-vehicle installation position of the display unit. As shown inFIG. 3B, two display units 16 are provided in the grille portion on thefront side of the vehicle 2. As described above, one display unit 16 ora plurality of display units 16 is provided on the front side of thevehicle 2.

The notification ECU 10 can cause the display unit 16 to display varioustraveling states of the vehicle 2 by changing the lighting state of thedisplay unit 16. For example, at the time of a deceleration state, thenotification ECU 10 causes the display unit 16 to flicker (example ofdeceleration displaying operation). At the time of the stopped state,the notification ECU 10 causes the display unit 16 to continue to emitlight (example of vehicle stoppage displaying operation) after stoppingflickering. At the time of the movement starting state, the notificationECU 10 causes the display unit 16 to flicker at a cycle faster thanlight flickering at the time of the deceleration state (example ofmovement starting displaying operation). Alternatively, at the time ofthe deceleration state or the stopped state, the notification ECU 10causes the display unit 16 to emit light of a color (safety color) suchas blue or green that gives a person a sense of safety (example ofdeceleration displaying operation and vehicle stoppage displayingoperation) and the notification ECU 10 causes the display unit 16 toemit light of an alert color such as red that makes a person cautious(example of movement starting displaying operation) at the time of themovement starting state. The notification ECU 10 may cause the displayunit 16 to emit light by using a first safety color (example ofdeceleration displaying operation) and a second safety color (example ofvehicle stoppage displaying operation) such that the deceleration stateand the stopped state can be distinguished from each other.Alternatively, at the time of the deceleration state, the notificationECU 10 may cause the display unit 16 to flicker at a high luminancelevel (example of deceleration displaying operation). At the time of thestopped state, the notification ECU 10 may cause the display unit 16 tocontinue to emit light at a low luminance level after stoppingflickering (example of vehicle stoppage displaying operation). At thetime of the movement starting state, the notification ECU 10 may causethe display unit 16 to continue to emit light at a luminance levelhigher than the luminance level of light at the time of the decelerationstate (example of movement starting displaying operation).

The notification ECU 10 is provided with a recognition unit 11, thedetermination unit 12, a calculation unit 13, a display controller 14(example of notification controller), and a vehicle stoppagedetermination unit 15.

The recognition unit 11 recognizes, based on the result of detectionperformed by the external sensor 3, the position of a pedestrian infront of the roadway on which the vehicle 2 travels. The function of therecognition unit 11 may be the same as the above-described pedestrianrecognition function of the autonomous driving ECU 8. The recognitionunit 11 determines whether an object detected by the external sensor 3is a pedestrian or not by using the pattern matching technique or thelike.

The determination unit 12 determines whether the pedestrian is asoon-to-cross pedestrian based on a distance between the position of thepedestrian recognized by the recognition unit 11 and the road on whichthe vehicle 2 travels. The function of the determination unit 12 may bethe same as the above-described pedestrian recognition function of theautonomous driving ECU 8. In an example shown in FIG. 2A, as with theautonomous driving ECU 8, the determination unit 12 determines that thepedestrian is the soon-to-cross pedestrian when the distance W is equalto or lower than a threshold value and determines that the pedestrian His not the soon-to-cross pedestrian when the distance W is not equal toor lower than the threshold value. The determination unit 12 maydetermine whether the pedestrian is the soon-to-cross pedestrian inconsideration of a direction in which the face of the pedestrian H facesand a direction in which the pedestrian H moves as well.

When the determination unit 12 determines that the pedestrian H is thesoon-to-cross pedestrian, the calculation unit 13 calculates, based onthe speed of the vehicle 2 during autonomous driving, the vehiclestoppage distance by which the vehicle 2 travels until the vehicle 2enters the stopped state while performing autonomous driving. Thefunction of the calculation unit 13 may be the same as theabove-described vehicle stoppage distance calculation function of theautonomous driving ECU 8. As with the autonomous driving ECU 8, thecalculation unit 13 can calculate, based on the vehicle speed measuredby the internal sensor 5 and the braking performance of the vehicle 2,the vehicle stoppage distance by which the vehicle 2 travels from thecurrent position until the vehicle 2 in a traveling state enters thestopped state, for example. The calculation unit 13 may acquire thebraking performance of the vehicle 2 from specification information ofthe vehicle 2 or from the autonomous driving ECU 8.

The display controller 14 determines information based on the vehiclestoppage distance calculated by the calculation unit 13, the position ofthe vehicle 2, and the position of the soon-to-cross pedestrian andcauses the display unit 16 to display the determined information. Thevehicle stoppage determination unit 15 determines whether the vehicle 2is in the stopped state. As with the autonomous driving ECU 8, thevehicle stoppage determination unit 15 determines that the vehicle 2 isin the stopped state when the vehicle speed measured by the internalsensor 5 is zero or falls in a predetermined range including zero.

Hereinafter, the display controller 14 will be described in detail. Anoperation performed by the display controller 14 when there is onesoon-to-cross pedestrian and an operation performed by the displaycontroller 14 when there is a plurality of soon-to-cross pedestrians aredifferent from each other. Therefore, hereinafter, an example in whichthere is one soon-to-cross pedestrian and an example in which there is aplurality of soon-to-cross pedestrians will be described.

FIG. 4 is a view illustrating an example of an operation of switchingbetween states of a displaying operation with respect to onesoon-to-cross pedestrian. In the example shown in FIG. 4, the vehicle 2is traveling on the road R and the external sensor 3 has detected amoving object on the position PH which is in front of the vehicle 2, ata time t1. In addition, the recognition unit 11 has recognized that themoving object is a pedestrian, the determination unit 12 has determinedthat the pedestrian is the soon-to-cross pedestrian H1, and thecalculation unit 13 has calculated a vehicle stoppage distance LA1. Inthis case, as with the autonomous driving ECU 8, the display controller14 determines the position P1 on the road R which corresponds to theposition PH of the soon-to-cross pedestrian H1. In addition, the displaycontroller 14 calculates a pedestrian-to-vehicle distance LB1 which is adistance between the position P corresponding to the soon-to-crosspedestrian H1 and the current position P0 of the vehicle 2 (for example,position of vehicle head of vehicle 2).

In an example shown in FIG. 4, the pedestrian-to-vehicle distance LB1 isgreater than the vehicle stoppage distance LA1. Therefore, the displaycontroller 14 determines that the autonomous driving ECU 8 will stop thevehicle 2 before the vehicle 2 reaches the position P1 corresponding tothe soon-to-cross pedestrian H1. That is, when the pedestrian-to-vehicledistance LB1 is equal to or greater than the vehicle stoppage distanceLA1, the display controller 14 determines information indicating thatthe vehicle 2 is in the middle of deceleration as information to bedisplayed on the display unit 16. When the autonomous driving ECU 8causes the vehicle 2 to start deceleration at a time t2, the displaycontroller 14 causes the display unit 16 to display no informationduring a period between the time t1 and the time t2 (decelerationdisplaying operation is OFF, passage displaying operation is OFF, andvehicle stoppage displaying operation is OFF) and causes the displayunit 16 to display the information indicating that the vehicle 2 is inthe middle of deceleration (deceleration displaying operation is ON,passage displaying operation is OFF, and vehicle stoppage displayingoperation is OFF) after the time t2. The display controller 14 maycontrol the display unit 16 based on time by being operated insynchronization with the autonomous driving ECU 8 and may change thestate of the deceleration displaying operation from an OFF state to anON state after confirming that the vehicle 2 is in the middle ofdeceleration based on the result of detection performed by the internalsensor 5.

When the vehicle stoppage determination unit 15 determines that thevehicle 2 is in the stopped state, the display controller 14 changesinformation to be displayed on the display unit 16 from the informationindicating that the vehicle 2 is in the middle of deceleration toinformation indicating that the vehicle 2 is in the stopped state. Whenthe vehicle stoppage determination unit 15 determines that the vehicle 2is in the stopped state at a time t4, the display controller 14 causesthe display unit 16 to stop displaying the information indicating thatthe vehicle 2 is in the middle of deceleration at the time t4 and causesthe display unit 16 to display the information indicating that thevehicle 2 is in the stopped state (deceleration displaying operation isON, passage displaying operation is OFF, and vehicle stoppage displayingoperation is OFF). Accordingly, the soon-to-cross pedestrian H1 cancross the road R after confirming a stoppage displaying operation.

FIG. 5 is a view illustrating another example of an operation ofswitching between states of a displaying operation with respect to onesoon-to-cross pedestrian. In the example shown in FIG. 5, the vehicle 2is traveling on the road R and the external sensor 3 has detected amoving object on the position PH which is in front of the vehicle 2, atthe time t1. In addition, the recognition unit 11 has recognized thatthe moving object is a pedestrian, the determination unit 12 hasdetermined that the pedestrian is the soon-to-cross pedestrian H1, andthe calculation unit 13 has calculated the vehicle stoppage distance LA.In this case, as with the autonomous driving ECU 8, the displaycontroller 14 determines the position P1 on the road R which correspondsto the position PH of the soon-to-cross pedestrian H1. In addition, thedisplay controller 14 calculates the pedestrian-to-vehicle distance LB1which is a distance between the position P1 corresponding to thesoon-to-cross pedestrian H1 and the current position P0 of the vehicle 2(for example, position of vehicle head of vehicle 2).

In an example shown in FIG. 5, the pedestrian-to-vehicle distance LB1 issmaller than the vehicle stoppage distance LA1. Therefore, the displaycontroller 14 determines that the vehicle 2 will pass through theposition P1 corresponding to the soon-to-cross pedestrian H1. That is,when the pedestrian-to-vehicle distance LB1 is smaller than the vehiclestoppage distance LA1, the display controller 14 determines informationindicating that the vehicle 2 is passing by the pedestrian asinformation to be displayed by the display unit 16. When the vehicle 2passes through the position P1 corresponding to the soon-to-crosspedestrian H1 at a time t3, the display controller 14 causes the displayunit 16 to display information indicating that the vehicle 2 is passingby the pedestrian during a period between the time t1 and the time t3(deceleration displaying operation is OFF, passage displaying operationis ON, and vehicle stoppage displaying operation is OFF) and causes thedisplay unit 16 to stop displaying the information indicating that thevehicle 2 is passing by the pedestrian (deceleration displayingoperation is OFF, passage displaying operation is OFF, and vehiclestoppage displaying operation is OFF) after the time t3. Accordingly,the soon-to-cross pedestrian H1 can understand that the vehicle 2 willnot stop in front of the soon-to-cross pedestrian H1.

FIG. 6 is a view illustrating an example of an operation of switchingbetween states of a displaying operation with respect to a plurality ofsoon-to-cross pedestrians. In the example shown in FIG. 6, the vehicle 2is traveling on the road R and the external sensor 3 has detected movingobjects on a position PH1 and a position PH2 which are in front of thevehicle 2, at the time t1. In addition, the recognition unit 11 hasrecognized that the moving objects are pedestrians and the determinationunit 12 has determined that the pedestrians are the first soon-to-crosspedestrian H1 and a second soon-to-cross pedestrian H2. The secondsoon-to-cross pedestrian H2 is positioned ahead of the firstsoon-to-cross pedestrian in the proceeding direction of the vehicle 2.In addition, the calculation unit 13 has calculated the vehicle stoppagedistance LA1. In this case, the display controller 14 determines theposition P1 on the road R which corresponds to the position PH1 of thefirst soon-to-cross pedestrian H1. Furthermore, the display controller14 determines a position P2 on the road R which corresponds to theposition PH2 of the second soon-to-cross pedestrian H2. In addition, thedisplay controller 14 calculates the first pedestrian-to-vehicledistance LB1 which is a distance between the position P1 correspondingto the first soon-to-cross pedestrian H1 and the current position P0 ofthe vehicle 2 (for example, position of vehicle head of vehicle 2). Inaddition, the display controller 14 calculates a secondpedestrian-to-vehicle distance LB2 which is a distance between theposition P2 corresponding to the second soon-to-cross pedestrian H2 andthe current position P0 of the vehicle 2 (for example, position ofvehicle head of vehicle 2).

In the example shown in FIG. 6, the first pedestrian-to-vehicle distanceLB1 is smaller than the vehicle stoppage distance LA1, and the secondpedestrian-to-vehicle distance LB2 is greater than the vehicle stoppagedistance LA1. Accordingly, the display controller 14 determines that thevehicle 2 passes through the position P1 corresponding to the firstsoon-to-cross pedestrian H1 and the vehicle 2 stops before reaching theposition P2 corresponding to the second soon-to-cross pedestrian H2. Inother words, the vehicle 2 starts deceleration at the time t2, passesthrough the position P1 corresponding to the first soon-to-crosspedestrian H1 at the time t3, and stops at the position p2 correspondingto the second soon-to-cross pedestrian H2 at the time t4.

When the first pedestrian-to-vehicle distance LB1 is smaller than thevehicle stoppage distance LA1 and the second pedestrian-to-vehicledistance LB2 is equal to or greater than the vehicle stoppage distanceLA1, the display controller 14 does not cause the display unit 16 todisplay the information indicating that the vehicle 2 is in the middleof deceleration before the vehicle 2 passes by the first soon-to-crosspedestrian H1. In other words, during a period between the time t2 andthe time t3, the information indicating that the vehicle 2 is in themiddle of deceleration is not displayed on the display unit 16 althoughthe vehicle 2 is in the middle of deceleration (deceleration displayingoperation is OFF). In addition, the display controller 14 causes thedisplay unit 16 to display the information indicating that the vehicle 2is in the middle of deceleration after the vehicle 2 passes by the firstsoon-to-cross pedestrian H1 (that is, after time t3) (decelerationdisplaying operation is ON). Accordingly, based on display on thedisplay unit 16, the first soon-to-cross pedestrian H1 can avoiderroneously recognizing that the vehicle 2 will stop in front of thefirst soon-to-cross pedestrian H1.

The display controller 14 may cause the display unit 16 to displayinformation indicating that the vehicle 2 is passing by the pedestrianduring a period between the time t2 and the time t3 in which thedeceleration displaying operation is OFF or a period between the time t1and the time t2, which is earlier than the period between the time t2and the time t3 (passage displaying operation is ON). Accordingly, it ispossible to notify the first soon-to-cross pedestrian H1 seeing thedisplay unit 16 that the vehicle 2 will pass by the first soon-to-crosspedestrian H1.

The operation of the display controller 14 at the time t4 is the same asillustrated in FIG. 4. The display controller 14 causes the display unit16 to stop displaying the information indicating that the vehicle 2 isin the middle of deceleration and causes the display unit 16 to displaythe information indicating that the vehicle 2 is in the stopped state(deceleration displaying operation is ON, passage displaying operationis OFF, and vehicle stoppage displaying operation is OFF).

Operation of Notification Device

FIGS. 7 and 8 are flowcharts illustrating an example of the operation ofthe notification device. A process as in the flowchart shown in FIG. 7is performed by the notification ECU 10 of the notification device 1.The notification ECU 10 starts the process as in the flowchart shown inFIG. 7 at a time when the autonomous driving ECU 8 starts the autonomousdriving.

As illustrated in FIG. 7, the recognition unit 11 of the notificationECU 10 recognizes whether an object in front of the vehicle 2 that isdetected by the external sensor 3 is a pedestrian or not as a pedestriandetecting process (S10). When the detected object is a pedestrian, therecognition unit 11 recognizes the position of the pedestrian. Then, thedisplay controller 14 of the notification ECU 10 determines whetherthere is an object recognized as a pedestrian in the pedestriandetecting process (S10), as a pedestrian determination process (S12).When the display controller 14 determines that there is an objectrecognized as a pedestrian (S12: YES), the process proceeds to asoon-to-cross pedestrian determination process (S14).

The determination unit 12 of the notification ECU 10 determines whetherthe pedestrian recognized in the pedestrian detecting process (S10) is asoon-to-cross pedestrian or not, as the soon-to-cross pedestriandetermination process (S14). The determination unit 12 determineswhether the pedestrian is the soon-to-cross pedestrian or not based onthe distance W between the position PH of the pedestrian H and the roadR on which the vehicle 2 travels (FIG. 2A).

When the determination unit 12 determines that the pedestrian is thesoon-to-cross pedestrian (S14: YES), the display controller 14determines whether the soon-to-cross pedestrians include first andsecond soon-to-cross pedestrians as a plurality determination (S16).When the display controller 14 determines that the soon-to-crosspedestrians include first and second soon-to-cross pedestrians as aplurality determination (S16: YES), the calculation unit 13 of thenotification ECU 10 calculates, based on the speed of the vehicle 2during autonomous driving, the vehicle stoppage distance LA1 by whichthe vehicle 2 travels until the vehicle 2 enters the stopped state whileperforming autonomous driving (FIG. 6) as a vehicle stoppage distancecalculation process (S18).

Next, the display controller 14 determines whether the firstpedestrian-to-vehicle distance LB1, which is a distance between thefirst soon-to-cross pedestrian H1 and the vehicle 2 is smaller than thevehicle stoppage distance LA1 as a first pedestrian-to-vehicledetermination process (S20) (FIG. 6). When the display controller 14determines that the first pedestrian-to-vehicle distance LB1 is smallerthan the vehicle stoppage distance LA1 (S20: YES), the vehicle 2 cannotenter the stopped state at the position P1 corresponding to the firstsoon-to-cross pedestrian H1. In this case, the display controller 14determines whether the second pedestrian-to-vehicle distance LB2, whichis a distance between the second soon-to-cross pedestrian H2 and thevehicle 2, is equal to or greater than the vehicle stoppage distance LA1or not as a second pedestrian-to-vehicle determination process (S22)(FIG. 6). When the display controller 14 determines that the secondpedestrian-to-vehicle distance LB2 is equal to or greater than thevehicle stoppage distance LA1 (S22: YES), the vehicle 2 can enter thestopped state at the position P2 corresponding to the secondsoon-to-cross pedestrian 12. In this case, the display controller 14sets a display change flag to [1] from [0] (initial value) as a flag ONprocess (S24). The display change flag is a flag for determining whetherto perform a process as in the flowchart shown in FIG. 8. As describedabove, when the vehicle 2 cannot enter the stopped state at the positionP1 corresponding to the first soon-to-cross pedestrian H1 and can enterthe stopped state at the position P2 corresponding to the secondsoon-to-cross pedestrian H2, the display controller 14 determines thatthe display state needs to be adjusted such that the first soon-to-crosspedestrian H1 does not misunderstand and sets the display change flag to[1].

When the display controller 14 determines that the soon-to-crosspedestrians do not include the first and second soon-to-crosspedestrians (S16: NO), there is no other soon-to-cross pedestrian thanthe first soon-to-cross pedestrian H1. In this case, the displaycontroller 14 performs a deceleration displaying process in accordancewith deceleration of the vehicle, as a display control process (S28).When the vehicle 2 can enter the stopped state at the position P1corresponding to the first soon-to-cross pedestrian H1, the displaycontroller 14 causes the display unit 16 to display the informationindicating that the vehicle 2 is in the middle of deceleration inaccordance with deceleration of the vehicle 2 (FIG. 4). When the vehicle2 cannot enter the stopped state at the position P1 corresponding to thefirst soon-to-cross pedestrian H1, the display controller 14 causes thedisplay unit 16 not to display the information indicating that thevehicle 2 is in the middle of deceleration in accordance withdeceleration of the vehicle 2 or causes the display unit 16 to displaythe information indicating that the vehicle 2 will pass the pedestrian(FIG. 5).

In addition, when the display controller 14 determines that the firstpedestrian-to-vehicle distance LB1 is not smaller than the vehiclestoppage distance LA1 (S20: NO), the vehicle 2 can enter the stoppedstate at the position P1 corresponding to the first soon-to-crosspedestrian H1 although there is a soon-to-cross pedestrian other thanthe first soon-to-cross pedestrian H1. Therefore, the display controller14 performs the deceleration displaying process in accordance with thedeceleration of the vehicle, as the display control process (S28). Thedisplay controller 14 causes the display unit 16 to display informationindicating that the vehicle 2 is in the middle of deceleration inaccordance with deceleration of the vehicle 2 (FIG. 4).

When the display controller 14 determines that the secondpedestrian-to-vehicle distance LB2 is not equal to or greater than thevehicle stoppage distance LA1 (S22: NO), the vehicle 2 cannot enter thestopped state at any of the position P1 corresponding to the firstsoon-to-cross pedestrian H1 and the position P2 corresponding to thesecond soon-to-cross pedestrian H2. Therefore, the display controller 14causes the display unit 16 to display the information indicating thatthe vehicle 2 will pass the pedestrian, as a passage displaying process(S26).

When the display controller 14 determines that there is no objectrecognized as a pedestrian (S12: NO), when the determination unit 12determines that the pedestrian is not the soon-to-cross pedestrian (S14:NO), when the flag ON process (S24) is finished, when the passagedisplaying process (S26) is finished, or when the display controlprocess (S28) is finished, the process as in the flowchart shown in FIG.7 is terminated. The notification ECU 10 starts the process as in theflowchart from the beginning when a termination condition is notsatisfied and the process as in the flowchart shown in FIG. 7 isterminated. Examples of the termination condition includes a conditionthat the autonomous driving is finished or a condition that a processstopping instruction is issued by a user.

A process as in the flowchart shown in FIG. 8 is performed by thenotification ECU 10 of the notification device 1. The notification ECU10 starts the process when the display change flag is set to [1] in theflag ON process (S24) in FIG. 7.

The display controller 14 of the notification ECU 10 determines whetherthe vehicle 2 has passed through the position P1 corresponding to thefirst soon-to-cross pedestrian H1, as passage determination (S30). Thedisplay controller 14 determines whether the vehicle 2 has passedthrough the position P1 or not based on the result of detectionperformed by the external sensor 3, for example. When the displaycontroller 14 determines that the vehicle 2 has not passed through theposition P1 corresponding to the first soon-to-cross pedestrian H1 (S30:NO), the display controller 14 causes the display unit 16 to display theinformation indicating that the vehicle 2 will pass by the pedestrianand causes the display unit 16 not to display the information indicatingthat the vehicle 2 is in the middle of deceleration, as the passagedisplaying process (S40) (FIG. 6). When the passage displaying process(S40) is finished, the process as in the flowchart shown in FIG. 8 isterminated. At this time, since the display change flag remains [1] andthus the display controller 14 performs the process as in the flowchartshown in FIG. 8 from the beginning. As described above, the displaycontroller 14 causes the display unit 16 to display the informationindicating passage of the vehicle 2 until the vehicle 2 passes by thefirst soon-to-cross pedestrian H1 and causes the display unit 16 not todisplay the information indicating that the vehicle 2 is in the middleof deceleration until the vehicle 2 passes by the first soon-to-crosspedestrian H1.

When the display controller 14 determines that the vehicle 2 has passedthrough the position P1 corresponding to the first soon-to-crosspedestrian H1 (S30: YES), the display controller 14 causes the displayunit 16 to display the information indicating that the vehicle 2 is inthe middle of deceleration, as the deceleration displaying process (S32)(FIG. 6). As described above, the display controller 14 causes thedisplay unit 16 to display the information indicating that the vehicle 2is in the middle of deceleration after the vehicle 2 passes by the firstsoon-to-cross pedestrian H1.

Next, the vehicle stoppage determination unit 15 of the notification ECU10 determines whether the vehicle 2 is in the stopped state, as avehicle stoppage determination process (S34). When the vehicle stoppagedetermination unit 15 determines that the vehicle 2 is not in thestopped state (S34: NO), the process as in the flowchart shown in FIG. 8is terminated. At this time, since the display change flag remains [1]and thus the display controller 14 performs the process as in theflowchart shown in FIG. 8 from the beginning. That is, the displaycontroller 14 repeats the deceleration displaying process (S32) untilthe vehicle 2 enters the stopped state.

When the vehicle stoppage determination unit 15 determines that thevehicle 2 is in the stopped state (S34: YES), the display controller 14changes information to be displayed by the display unit 16 from theinformation indicating that the vehicle 2 is in the middle ofdeceleration to the information indicating that the vehicle 2 is in thestopped state, as a vehicle stoppage displaying process (S36). Next, thedisplay controller 14 sets the display change flag to [0] from [1] as aflag OFF process (S38). When the flag OFF process (S38) is finished, theprocess as in the flowchart shown in FIG. 8 is terminated. At this time,since the display change flag is [0], the display controller 14 do notrepeats the process as in the flowchart shown in FIG. 8.

In the case of the notification device 1 as described above, when thefirst pedestrian-to-vehicle distance LB1 (distance between vehicle 2 andfirst soon-to-cross pedestrian H1) is smaller than the vehicle stoppagedistance LA1 and the second pedestrian-to-vehicle distance LB2 (distancebetween vehicle 2 and second soon-to-cross pedestrian H2) is equal to orgreater than the vehicle stoppage distance LA1, notification withrespect to the outside of the vehicle is not performed by means of thedeceleration displaying operation (information indicating that vehicle 2is in middle of deceleration) until the vehicle 2 passes by the firstsoon-to-cross pedestrian H1 and notification is performed by means ofthe deceleration displaying operation after the vehicle 2 passes by thefirst soon-to-cross pedestrian H1. As described above, the vehicle 2 donot start notification by means of the deceleration displaying operationat a position in front of the first soon-to-cross pedestrian H1 at whichthe vehicle 2 will not stop. Therefore, the first soon-to-crosspedestrian H1 can avoid erroneously recognizing that the vehicle 2 willstop in front of the first soon-to-cross pedestrian H1. In addition,after the vehicle 2 passes by the first soon-to-cross pedestrian H1,notification is performed by means of the deceleration displayingoperation. Therefore, correct information indicating that the vehiclewill stop in front of the second soon-to-cross pedestrian can beappropriately provided to the second soon-to-cross pedestrian H2.Accordingly, with the notification device 1, it is possible to performnotification without confusing any one of the first soon-to-crosspedestrian H1 and the second soon-to-cross pedestrian H2.

In the case of the notification device 1, notification with the passagedisplaying operation is performed with respect to the firstsoon-to-cross pedestrian H1, who is not the target of notification withthe deceleration displaying operation. Therefore, the firstsoon-to-cross pedestrian H1 is appropriately notified of a futurebehavior of the vehicle 2, that is, a behavior of passing by the firstsoon-to-cross pedestrian H1 without stopping in front of the firstsoon-to-cross pedestrian H1. Therefore, with the notification device 1,it is possible to avoid confusing the first soon-to-cross pedestrian H1.

In the case of the notification device 1, when a determination is madethat the vehicle 2 is in the stopped state, information is changed fromthe deceleration displaying operation to the vehicle stoppage displayingoperation. Therefore, it is possible for a pedestrian to clearlydistinguish between a state where the vehicle is in the middle ofdeceleration and a state where the vehicle is in the stopped state.

Hereinabove, various exemplary embodiments have been described. However,the disclosure is not limited to the above-described exemplaryembodiments and various omissions, substitutions, and modifications maybe made.

For example, the display unit 16 do not need to be provided outside thevehicle 2 and the display unit 16 may be provided at a position insidethe vehicle such as a position inward of the windshield as long as it ispossible to perform notification about information with respect to theoutside of the vehicle. In addition, the display unit 16 is not limitedto a lamp and may be a display device. The point is that the displayunit 16 may be any device emitting light. When a display device isadopted as the display unit 16, the notification device 1 may expressdeceleration, vehicle stoppage, and movement start using letters insteadof light. The notification device 1 has the same effect as the abovedescribed exemplary embodiments even when notification is performed withletter information. In addition, for the notification device 1, aspeaker outputting a sound may be used instead of the display unit 16.The notification device 1 may use a pseudo engine sound as anotification sound. The notification device 1 has the same effect as theabove described exemplary embodiments even when notification isperformed with sound information.

The functions of the recognition unit 11, the determination unit 12, andthe calculation unit 13 overlap with that of the autonomous driving ECU8. Therefore, a configuration in which the result of calculationperformed by the autonomous driving ECU 8 is acquired by thenotification ECU 10 may also be adopted. That is, a part of thefunctions of the autonomous driving ECU 8 and the display controller 14may constitute the notification device 1.

The vehicle stoppage distance calculation process (S18) in FIG. 7 may beperformed at any time between the start of the process in FIG. 7 and thefirst pedestrian-to-vehicle determination process (S20). In the passagedisplaying process (S40) in FIG. 8, the passage displaying operation maybe omitted. In addition, the notification device 1 may not be providedwith the vehicle stoppage determination unit 15.

What is claimed is:
 1. A notification device provided in a vehicleperforming autonomous driving and configured to notify pedestrians ofinformation, the device comprising: an electronic control unitconfigured to: recognize, based on a result of detection performed by anexternal sensor, positions of the pedestrians in front of a roadway onwhich the vehicle travels; determine, based on a distance between thepositions of the pedestrians recognized by the electronic control unitand a road on which the vehicle travels, whether the pedestrians aresoon-to-cross pedestrians; calculate, based on a speed of the vehicleduring autonomous driving, a vehicle stoppage distance by which thevehicle travels until the vehicle enters a stopped state whileperforming autonomous driving when the electronic control unitdetermines that the pedestrians are the soon-to-cross pedestrians; anddetermine the information based on the vehicle stoppage distancecalculated by the electronic control unit, a position of the vehicle,and the positions of the soon-to-cross pedestrians and to cause adisplay unit to perform notification about the determined information;and the display unit provided in the vehicle and configured to performnotification about the information with respect to an outside of thevehicle; and wherein the soon-to-cross pedestrians include a firstsoon-to-cross pedestrian and a second soon-to-cross pedestrianpositioned ahead of the first soon-to-cross pedestrian in a proceedingdirection of the vehicle, and the electronic control unit is configuredto cause the display unit not to perform notification about informationindicating that the vehicle is in the middle of deceleration until thevehicle passes by the first soon-to-cross pedestrian and to cause thedisplay unit to perform notification about information indicating thatthe vehicle is in the middle of deceleration after the vehicle passes bythe first soon-to-cross pedestrian when a distance between the vehicleand the first soon-to-cross pedestrian is smaller than the vehiclestoppage distance and a distance between the vehicle and the secondsoon-to-cross pedestrian is equal to or greater than the vehiclestoppage distance.
 2. The notification device according to claim 1,wherein the electronic control unit is configured to cause the displayunit to perform notification about information indicating passage of thevehicle until the vehicle passes by the first soon-to-cross pedestrian.3. The notification device according to claim 1, wherein the electroniccontrol unit is configured to: determine whether the vehicle is in astopped state, and change information, about which the display unitperforms notification, from information indicating that the vehicle isin the middle of deceleration to information indicating that the vehicleis in the stopped state when the electronic control unit determines thatthe vehicle is in the stopped state.
 4. The notification deviceaccording to claim 1, wherein the display unit is configured to displaythe information as notification about the information, and theelectronic control unit is configured to control a displaying operationof the display unit.